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annotate tomsfastmath/src/bit/fp_lshd.c @ 645:8622ee48fab5 dropbear-tfm

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- Work around broken asm constraint behaviour on 32bit x86 OS X
author Matt Johnston <matt@ucc.asn.au>
date Wed, 30 Nov 2011 22:27:26 +0800
parents a362b62d38b2
children
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a362b62d38b2 Add tomsfastmath from git rev bfa4582842bc3bab42e4be4aed5703437049502a
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1 /* TomsFastMath, a fast ISO C bignum library.
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2 *
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3 * This project is meant to fill in where LibTomMath
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4 * falls short. That is speed ;-)
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5 *
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6 * This project is public domain and free for all purposes.
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7 *
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8 * Tom St Denis, [email protected]
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9 */
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10 #include <tfm.h>
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12 void fp_lshd(fp_int *a, int x)
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13 {
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14 int y;
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16 /* move up and truncate as required */
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17 y = MIN(a->used + x - 1, (int)(FP_SIZE-1));
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19 /* store new size */
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20 a->used = y + 1;
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22 /* move digits */
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23 for (; y >= x; y--) {
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24 a->dp[y] = a->dp[y-x];
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25 }
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27 /* zero lower digits */
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28 for (; y >= 0; y--) {
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29 a->dp[y] = 0;
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30 }
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32 /* clamp digits */
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33 fp_clamp(a);
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34 }
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36 /* $Source$ */
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37 /* $Revision$ */
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38 /* $Date$ */